| parallel | | set of points in a plane that are the same distance from the center |
| congruent | | exact location in space |
| area | | angle that measures 90 degrees |
| interior | | angle whose measures greater that 90 but less than 180 degrees |
| pi | | line segment that passes through the center of a circle and has endpoint on the circle |
| octagon | | triangle with two congruent sides |
| heptagon | | line segment with one endpoint in the center of a circle and the other endpoint on the circle |
| diameter | | line segment that joins two points on the circumference of a circle |
| equilateral | | having same shape and same size |
| corresponding | | angles formed by two lines entersected by a third line |
| hexagon | | three-sided polygon |
| vertex | | pair of opposite congruent angles formed by intersecting lines |
| chord | | angle that measures less than 90 degrees |
| rhombus | | object or structure looks the same after a specific change occurs |
| pentagon | | number of square units needed cover a given surface |
| perimeter | | eight-sided polygon |
| obtuse | | distance around a circle |
| isosceles | | matching two or more angles or polygons |
| exterior | | quadrilateral with exactly one pair of parallel sides |
| acute | | four-sided polygon |
| symmetrical | | lines that cross at exactly one point |
| scalene | | line that cuts across two or more parallel lines at different points |
| trapezoid | | nine-sided polygon |
| similar | | straight path that extends without end in opposite directions |
| decagon | | having same shape but not necessarily the same size |
| triangle | | ratio of circumference to the length of its diameter; 3.14 |
| vertical | | six-sided polygon |
| transversal | | point where two sides intersect on angle or polygon |
| alternate | | distance around a polygon |
| perpendicular | | parallelogram with all sides congruent |
| line | | lines in a plane that do not intersect |
| quadrilateral | | part of a line that starts in one point and continues forever |
| nonagon | | angles on the outer sides of two lines intersected by a third line |
| radius | | ten-sided polygon |
| circumference | | five-sided polygon |
| right | | triangle with three congruent sides |
| ray | | triangle with no congruent sides |
| circle | | lines that lie in different planes that are neither parallel or perpendicular |
| skew | | lines that intersect to form right angles |
| intersecting | | angles on the inner sides of two lines intersected by a third line |
| point | | seven-sided polygon |
